Project

# Title Team Members TA Documents Sponsor
91 Automatic Bike Collision Prevention System
 Charlie Wang
Nathan Zhu
Rahul Nayak
 Frey Zhao proposal1.pdf
# Automatic Bike Collision Prevention System

Team Members:
- Rahul Nayak (rn8)
- Charlie Wang (cgwang3)
- Nathan Zhu (nyzhu2)

# Problem

Active pathways like campus sidewalks create high risk scenarios for cyclists and passerby due to oblivious pedestrians and distracted riding. Traditional bicycle bells are reactive rather than proactive, requiring both the cyclist to recognize a potential collision and react by ringing the bell, and pedestrians to acknowledge the bell and move out of the way. The total time to prevent collision can be lengthened if the cyclist’s reaction time was not a consideration. As such, there is a need for an automated alert system that is able to identify and distinguish potential collision hazards before they occur.

# Solution

We will create a handlebar-mounted safety system using three mmWave radar sensors to act as a peripheral vision of sorts. The sensors will be set up such that we have a center sensor, and left and right sensors. The system performs spatial gating, where detections transitioning from peripheral radar sectors into the forward sector are classified as hazards, while detections only in the peripheral radar sectors are ignored. We estimate a time to collision depending on the current distance detected and the distance from past readings, and ring the bell at different volumes accordingly.

# Solution Components

## Subsystem 1: Power

Provide regulated power and system status feedback.

Components:

- Li-ion 18650 Battery: High capacity power source.
- Buck-Boost Converter: Stable 5V/3.3V regulation.
- Status LEDs: Indicators to indicate if the system is on, sensitivity level, and if an object is detected.
- Sensitivity Potentiometer: Allows the rider to adjust the magnitude threshold for different environments.

## Subsystem 2: Radar Sensor Array

Function: Detect object distance.

Components:

- Three HLK-LD2410 24GHz mmWave Radar Modules
- Configuration: 1 center (0°), 2 side angled (30°)
- To create distinct sensors, small 3D printed shields will be set to limit field of view and prevent cross-talking.
- This triangular configuration allows for section-based filtering.
- Due to limited UARTs on the ESP32, the radars should be checked one at a time in a very fast, cyclical manner, which would also help prevent crosstalking.

## Subsystem 3: Processing

Function: Filter noise and determine collision likeliness.

Components:
- ESP32 Microcontroller: UART connection with Radar sensors
- Magnitude thresholding: Ignore low energy reflections such as from pavement or small non-collision objects.
- Time-To-Collision algorithm: Estimate how long it will take until a collision occurs.

## Subsystem 4: Alert System

Function: Create a gradually audible ringing sound depending on the expected collision time.

Components:
- Piezo Buzzer (PS1240): Use Pulse Width Modulation to increase beep frequency
- Three alert stages

# Criterion For Success

The project will be considered successful if all criteria below are met:
- Range performance: Reliably detect objects from 5 meters away.
- Low latency: Detection to audio output is less than 150ms.
- Form factor: Device is compact enough to mount on handlebars.
- False-positive mitigation: Thresholding prevents alarm from triggering for ground objects and other non hazards.
- Peripheral vision: Device is able to detect objects in peripheral vision and keep track of these objects moving into the sight of the center sensor.
- Battery life: Battery should last at least 8 hours on a single charge.

Digitizing the Restaurant with Network-Enabled Smart Tables

Andrew Chen, Eric Ong, Can Zhou

Featured Project

# Students

Andrew Chen - andrew6

Eric Ong - eong3

Can Zhou - czhou34

# Problem:

The restaurant industry relies on relatively archaic methods of management and customer service. Internal restaurant computer systems are limited and rely on staff members to monitor customer status. Restaurants lack contact-free transactions for clientele.

# Solution Overview:

Our solution to this problem is to develop a standalone LAN restaurant network system to manage customer status and occupancy for restaurants without the need for personnel to monitor it manually. Along with this, to accommodate for contact-free interactions, we propose a system for payment methods. To address customer preferences, we will provide height accommodation built into the table for different types of people.

# Solution Components:

[Self-adjusting Customer Height Accommodation] - The table will be held up with a linear actuator, thus allowing for the overall height to be adjustable. The table will adjust its height accordingly to the customers’ heights once they sit down. We plan to make the table adjust the table’s height by measuring the distance between the bottom of the table with the customer’s knees when they are sitting down using ultrasonic sensors.

[NFC Payment and Card Reader Payment] - The table will have NFC reader and magstripe reader for contactless delivery. The payment data will be sent to the centralized hub for processing and confirmation.

[Table Pressure Sensor] - The status of a table will be gauged based on the amount of weight on the physical table itself. An occupied (or even just an unoccupied and dirty table) will be marked as such since the weight of excess food, water, plates, and whatever else the customer may bring will be measured by this pressure sensor.

[Computer Mesh Network] - We plan to create a mesh network of raspberry pi’s to track the status of tables in a restaurant. This network will communicate via some form of wireless communication (Wi-FI, bluetooth, or Zigbee).

# Criterion for Success:

This project seeks to create a solution in which restaurants can minimize customer interaction with features that accommodate individual needs, such as the height of the table and payment methods. This project will be considered successful with a working prototype that includes features that may be included in an actual restaurant setting.

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